Light weight, hinged self-closing container covers and combination flex-torsion springs for use with such covers

ABSTRACT

Combination flex and torsion springs for use with light weight covers for containers having self-closing gates, the springs operatively connecting the gates to surrounding cover portions. A tri-fold seam including a frangible seam works cooperatively with the flex-torsion springs to implement three modes of operation of the gates. In a first mode, the gate returns to a reclosed orientation after removal of downward pressure. Further pressure on the gate engages a toggle operation that locks the gate open. In a third mode, if the gate is pushed even further downward, the toggle mechanism is defeated and the combination flex-torsion spring is forced past its elastic limit and the gate remains in a permanently open orientation. The flex-torsion springs in accordance with the invention may be fabricated from aluminum sheet stock or spring wire.

RELATED APPLICATIONS

This application is related to U.S. patent application Ser. No. 13/477,984 for RESEALABLE CONTAINER HAVING FRANGIBLE PORTION AND HINGED TOP filed May 22, 2012 that was in turn a continuation-in-part of the U.S. patent application Ser. No. 12/195,372 for LIGHT WEIGHT HINGED TOP filed Aug. 20, 2008, now issued as U.S. Pat. No. 8,215,513. Both applications and the issued patent are included herein in their entirety by reference.

FIELD OF THE INVENTION

The invention pertains to container tops and, more particularly, to a light weight top with a frangible, self-closing gate that occupies a large percentage of the area of the container top supported by a combination flex and torsion spring.

BACKGROUND OF THE INVENTION

For many years, manufacturers of cans, particularly aluminum beverage containers have searched for a way to replace pull tab opening mechanisms universally used in the beverage industry. Variations of pull tab opening mechanisms are universally used throughout the world but have two primary deficiencies. First, with some pull tab designs, the tab may fall into the beverage container and potentially become a swallowing hazard. Second, once opened, pull tab opening mechanisms are not easily resealed. Beverages, particularly carbonated beverages like beer and soft drinks rapidly lose their effervescence as the entrained carbon dioxide is released from the beverage and passes into the air surrounding the beverage container.

Additionally, pull tab opening mechanisms typically require at least some finger/hand strength to open the container. The opening process may present difficulties to potential users who do not possess sufficient finger/hand strength.

Also, pull tab tops of the prior art require a quantity of metal, generally aluminum, that might be reduced in a better design, and are process intensive in their manufacture.

In the previously filed included by reference applications, covers having relatively small self-closing gate openings have been disclosed. The beverage industry, in particular, is clamoring for containers having self-closing covers but having larger openings. No such container covers have heretofore been available.

It would, therefore, be desirable to create an easily openable container cover that eliminates the possibility of any portion of the pull tab opening mechanism from detaching from the can and falling into the contents and, in addition, it would be desirable to create a self-closing cover so as to trap carbon dioxide from escaping from the beverage into the surrounding air. It would further be desirable to make the container top light weight to minimize the amount of metal needed to form the top. It would be further desirable to provide self-closing covers having openable gates occupying up to 100% of the surface area including the chuck walls of the container top.

SUMMARY OF THE INVENTION

In accordance with the present invention there are provided light weight, covers for containers having reclosable gate or dome areas that are operatively connected to outer portions of the cover by a combination flex-torsion spring. A unique tri-fold seam including a frangible seam portion forms an inverted flange that works cooperatively with the combination flex-torsion spring to implement three modes of operation of the openable gates. In a first mode, after the gate is initially opened by downward directed pressure, for example a tap on the dome or gate by the heal of the palm of a user's hand, the gate returns to a reclosed orientation. Further downward pressure on the gate pushes it further into the container to which the novel cover is attached whereat a toggle operation locks the gate in the open position. An action such as swirling the container contents against the gate, overcome the toggle and the gate again returns to a reclosed orientation. Finally, if the gate is pushed even further downward, the toggle mechanism is defeated and the combination flex-torsion spring is forced past its elastic limit and the gate remains in a permanently open orientation. The novel covers in accordance with the invention may be fabricated to be compatible with current production equipment and practices. The novel covers eliminate the pull tab construction of the prior art and allow comparable containers to be produced using less material than prior art containers. Multiple designs for combination flex-torsion springs are also provided, including extremely narrow designs that allow the gate to occupy nearly 100% of the cover area inside or outside the chuck walls.

It is, therefore, an object of the invention to provide a lightweight, self-closing cover for a container.

It is another object of the invention to provide a lightweight, self-closing cover for a container that utilizes a flex-torsion spring to effect reclosing.

It is an additional object of the invention to provide a lightweight, self-closing cover for a container that utilizes a flex-torsion spring to provide three modes of operation of the gate: a first mode allowing the gate to close upon release of the downward pressure upon it; a second mode wherein the gate remains open when the downward pressure is released but recloses when tapped or otherwise stimulated; and a third mode where the gate remains permanently open.

It is a further object of the invention to provide a lightweight, self-closing top for a container wherein the gate occupies up to 100% of the cover area inside or outside the chuck walls.

It is a still further object of the invention to provide a lightweight, self-closing top for a container that may be formed using smaller amounts of aluminum or other material than container covers of the prior art.

It is yet another object of the invention to provide a lightweight, self-closing top for a container that may be attached to containers using existing machinery without modification.

BRIEF DESCRIPTION OF THE DRAWINGS

Various objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein:

FIG. 1A is a side elevational, cross-sectional, schematic view of a light weight, hinged self-closing container cover having a combination flex and torsion spring in a closed configuration in accordance with the invention;

FIGS. 1B and 1C are enlarged portions of the light weight, hinged self-closing container cover having a combination flex and torsion spring of FIG. 1A;

FIG. 1D is another enlarged portion of the light weight, hinged self-closing container cover of FIG. 1C before separation;

FIG. 1E is another enlarged portion of the light weight, hinged self-closing container cover of FIG. 1C as separation begins;

FIG. 1F is a bottom plan view of the cover of FIG. 1A showing the location of the hinged spring;

FIG. 2 is a side elevational, cross-sectional, perspective, schematic view of the light weight, hinged self-closing container cover having a combination flex and torsion spring of FIG. 1A;

FIGS. 3A and 3B are top and bottom perspective, schematic views of combination flex and torsion spring attached to cover of FIG. 1A;

FIG. 4A is a bottom plan, schematic view of a hypothetical container top having a gate and six beaks equidistantly spaced along a frangible seam;

FIGS. 4B-4I are side elevational, cross-sectional, schematic views of a simplified light weight, hinged, self-closing container cover of FIG. 1A in various stages of opening and reclosing;

FIG. 4J is an enlarged portion of the cover of FIG. 4D showing the interaction of the combination flex and torsion spring and showing a flange formed by the tri-fold seam;

FIG. 4K is a partial side elevational, cross-sectional view of a portion of the cover of FIG. 4 a showing a detailed schematic view of one of the breaks;

FIG. 5A is a top plan, schematic view of a container cover having a large (approximately 90% or larger) gate

FIG. 5B is a partial side elevational, cross-sectional view of the cover of FIG. 5A;

FIG. 5C is an enlarged portion of the view of FIG. 5B showing a detailed view of the triple fold flange showing the frangible seam/tear line;

FIG. 5D is a partial side elevational, cross-sectional view of the cover of FIG. 5A showing a triple fold seam contained within a chuck wall, and with a closed gate;

FIG. 5E is a partial side elevational, cross-sectional view of the cover of

FIG. 5D showing a triple fold seam contained within a chuck wall and with a gate partially open;

FIG. 5F is a partial side elevational, cross-sectional view of the cover of FIG. 5D showing a triple fold seam contained within a chuck wall and with a gate fully open;

FIG. 6A is a bottom perspective, schematic view of a first embodiment of a combination flex-torsion spring for use in conjunction with the cover of FIG. 5A;

FIG. 6B is a bottom plan view of the cover of FIG. 5A with the combination flex-torsion spring of FIG. 6A coupled thereto;

FIG. 7A is a bottom perspective, schematic view of an alternate embodiment of a combination flex-torsion spring for use in conjunction with the cover of FIG. 5A;

FIG. 7B is a bottom plan view of the cover of FIG. 5A with the combination flex-torsion spring of FIG. 7A coupled thereto;

FIG. 8 is a bottom perspective view of a combination flex-torsion spring formed having the same general shape as the spring of FIG. 7A but formed from spring wire;

FIG. 9A is a top perspective, schematic view of another implementation of a combination flex-torsion spring intended for use with smaller gates; and

FIG. 9B is a bottom plan, schematic view of a cover utilizing the combination flex-torsion spring of FIG. 9A.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention provides light weight, hinged, self-closing container covers having combination flex and torsion (flex-torsion) springs. Flex-torsion springs exhibit two modes of operation: that of a traditional flex spring combined with that of a traditional torsion spring. While applicable to many different sizes and styles of container, the novel cover of the present invention is particularly useful for beverage containers. In addition, multiple combination flex-torsion spring designs are provided.

In my previous work, light weight, self-closing covers having several sizes and configurations were disclosed. However, none of the previously disclosed designs allowed for large gate openings, for example, gate openings that covered 90% or more of the cover real estate within or including the outer chuck walls.

Every self-closing cover requires a spring to provide a restoring force to close the gate once the gate has been opened. In the previously disclosed designs, springs having only a flexing mode of operation have been utilized. These types of spring typically occupy too much space to allow practical covers having self-closing, large gate openings to be constructed. As used herein, the term large gate openings is used to refer to gate openings of approximately 90% or more of the surface area of the cover included within the chuck walls or, in some cases, including the chuck walls.

However, it should be noted that gate sizes even larger than 90% are possible by careful spring design and integrating at least a portion of the spring inside the raised (or depressed) ridge that is a chuck wall. Such designs are referred to as “inside a chuck wall”. The term “within the chuck walls” refers to designs where the spring and associated mechansims are located within the cover space defined by the perimeter chuck wall but NOT physically inside a chuck wall.

Flex springs generate their restorative force by merely moving in a single plane. A force applied to a flex spring pushes it from an original position to a new position. Assuming that the spring has not been pushed beyond its elastic limit and deformed, once the force is released, the spring attempts to return to its original position and in the process, provides a restorative force. The size of the flex spring and the material from which it is made determines the amount of restorative force that the spring can generate.

Spring designs that generate restoring forces from more than one modality of operation, for example, the flex-torsion spring used in the designs of the present invention may be constructed more compactly. In such designs, only a portion of the restoring force is derived from the flexing action of the spring. Another portion of the necessary restoring force is derived from the twisting/untwisting motion of a torsion component of the flex-torsion spring. Consequently, springs having compact flex portions and thin, curved elongated arms extending outwardly from the central or flex portion of the flex-torsion spring may be constructed. The thin, curved elongated arms that may move with a twisting motion may provide a large portion of the restoring force necessary to close, for example, the gate of a large gate self-closing cover.

Referring first to FIG. 1A, there is shown a side elevational, cross-sectional, schematic view of a simplified light weight, hinged, self-closing container cover having a combination torsion and flex spring, generally at reference number 100. Cover 100 is shown before attachment to a container, not shown, and in a sealed (i.e., unopened) state. Further, cover 100 is a simplified design used to illustrate the operation of the combination flex and torsion spring. More complex covers using combination flex and torsion springs are described and discussed hereinbelow.

Cover 100 consists of a seaming panel (shown as seaming panel segments 102 a, 102 b having respective distal ends 104 a, 104 b forming a so-called curl. Distal ends 104 a, 104 b are adapted for attachment to upstanding walls 118 a, 118 b (FIG. 4B) of a container, not shown, thereby forming a peripheral seam or seal, not specifically identified.

It should be noted that any container discussed or shown forms no part of the present invention and such containers when shown and/or discussed are presented only to better describe cover 100.

Intermediate sloping panel segments 134 a, 134 b connect seaming panel segments 102 a, 102 b to outer countersink walls 114 a, 114 b. Countersinks 116 a, 116 b are formed by outer countersink walls 114 a, connected to respective countersink inner walls 114 b.

Inner countersink walls 114 b connect to respective top panel portions 136 a, 136 b that, in turn, connect to respective triple fold seams 106 a, 106 b.

A Triple fold seam 112 surrounds a central gate or dome 108.

While in the cross-sectional view of FIG. 1A, seaming panel portions 102 a, 102 b, distal ends 104 a, 104 b, intermediate sloping sections 134 a, 134 b, and top panel portions 136 a. 136 b are labeled for purposes of discussion, cover 100 is typically a circular structure and seaming panel 102 represented as seaming panel portions 102 a, 102 b, etc. are in reality, continuous circular structures best seen in FIG. 2 until gate 108 is opened.

Flanges 106 a, 106 b are shown in more detail in FIGS. 1B and 1C, respectively, and are discussed in more detail hereinbelow.

While gate 108 is shown as a substantially flat surface, it will be recognized that gate 108 may be replaced by an upwardly (or in alternate embodiments, downwardly directed) curvilinear structure as shown in alternate gate or dome 108′.

A combination flex-torsion spring 112 provides support and closure force for gate 108 after the gate has been opened.

Flex-torsion spring 112 is typically formed from aluminum, often the same material from which the remainder of cover 100 and the container are formed. A typical aluminum alloy found suitable for the application is 5052-H19 and a thickness in the range of approximately 0.006 to 0.007 inch. It will be recognized that other aluminum alloys and/or material thicknesses may be substituted to meet particular operating circumstance or design. Consequently, the invention is not considered limited the alloy or thickness range chosen for purposes of disclosure. Rather, the invention is intended to include other metals, alloys, and/or thicknesses.

Referring now also to FIGS. 1B and 1C, there are shown enlarged drawings of portions of triple fold flanges 106 a, 106 b, respectively. Of particular interest is the coined frangible seam 110 a, 110 b formed in respective flanges 106 a, 106 b. Frangible seam 110 a, 110 b defines a tear line completely around gate 108 that allows separation of gate 108 from panel 102 as gate 108 of cover 100 is “opened”. While frangible seams 110 a, 110 b are typically formed using a coining process, it will be recognized by those of skill in the art that alternate formation processes may be utilized. The opening process is discussed in more detail hereinbelow.

It will be recognized that the concept of “beaks” has been discussed extensively in my forgoing work, U.S. Pat. No. 8,215,513, included herein by reference. Beaks, so named for their tapered, pointed shape, or other similar structures, none shown, are provided at one or more points along the frangible seam 110 a, 110 b to facilitate an initial rupture of the frangible seam. Providing beaks or similar structures reduces the applied force required to open the container by separating the frangible seam (i.e., the tear line). With larger, round gate in accordance with the present invention, the necessity for more than two beaks is envisioned. A preliminary analysis indicates that five to seven beaks disposed circumferentially around large round gates proximate the frangible seam may be required to ensure proper opening,

Referring now also to FIG. 1D, there is shown an additional cross-sectional, schematic view of the seam of FIG. 1C. Frangible seam 110 b is thinned adjacent curved structures 150 a, 150B forming an indentation 152 in frangible seam 110 b. As depicted in FIG. 1D, frangible seam 110 b has not yet begun to rupture.

Referring now also to FIG. 1E, there is shown an additional cross-sectional, schematic view of the seam of FIG. 1C but showing that frangible seam 110 b has begun to rupture adjacent curved structures 150 a, 150 b. Portions 154 a, 154 b are shown separated with respect to one another.

Referring now also to FIG. 1F, there is shown a bottom plan, schematic view of cover 100. Notable in FIG. 1F are optional fasteners or stakes 144 and 146. First and second optional fasteners or stakes 144 attach opposing arcuate side arms 126 a, 126 b to gate 108 through a corresponding one of optional holes 130 a, 130 b. Another optional fastener or stake 146 through hole 122 in central portion 120 not shown fastens spring 112 to panel 136. Holes 130 a, 130 b, and 122 are best seen in FIGS. 3A and 3B.

Referring now also to FIG. 2, there is shown a side elevational, cross-sectional, perspective, schematic view of the simplified light weight, hinged self-closing container cover having a combination flex-torsion spring 112 of FIG. 1A. In FIG. 2, the relationship of combination flex-torsion spring 112 to the panel 136 and the gate 108 is better illustrated.

Referring now also to FIGS. 3A and 3B, there are shown top and bottom perspective, schematic views of combination flex-torsion spring 112.

Spring 112 has a substantially flat square central portion 120, typically having a central hole 122 therethrough. Central portion 120 has an inward facing camming detent structure 124 disposed on a front edge, not identified, perpendicular to the flat surface, not identified, of central portion 120. Inward facing refers to the direction toward the center of cover 100. The functions of camming detent structure 124 are discussed in more detail hereinbelow.

A pair of opposing arcuate side arms 126 a, 126 b project outward from respective sides of the flat portion of central portion 120. Opposing arcuate side arms 126 a, 126 b have a short curved section 132 a, 132 b, respectively, adjacent central portion 120 that allows the major surface of each to be raised to approximately the same height as that of camming detent structure 124.

Each of opposing arcuate side arms 126 a, 126 b has a flattened portion 128 a, 128 b adjacent their respective distal ends, not specifically identified. Flattened portions 128 a, 128 b may be off-set or stepped up or down to a different plane from the remainder of side arms 126 a and 126 b. An optional through hole 130 a, 130 b may be centrally located in respective flattened portions 128 a, 128 b.

Referring now also to FIG. 4A, there is shown a bottom plan, schematic view of a hypothetical container top having a gate 108 with six beaks 158 equidistantly spaced around a frangible seam 110 separating gate 108 from an adjacent panel 136 at locations 156. As may be seen in FIG. 4K, frangible seam 110 is surrounded by weakened areas 148.

FIG. 4K is a partial side elevational, cross-sectional view of a portion of the cover of FIG. 4 a showing a detailed schematic view of one of the breaks 158 shown in FIG. 4A at locations 156 around the perimeter of gate 108. In FIG. 4A, frangible seam or tear line 110 is surrounded on each side by two weakened areas 148 along curved areas adjacent 156;

As mentioned, beak structures having many different shapes, sizes, and dispositions capable of facilitating an initial rupture of frangible seam 110 will be recognized by those of skill in the art. Consequently, the invention is not considered limited to any particular quantity of a particular shape, size, and orientation of a beak structure. The invention is intended to include any and all suitable replacement structures for the beaks disclosed in the included by reference '513 patent.

With larger, especially round gates in accordance with the invention, the downwardly directed opening force applied to gate 108 may strike gate 108 in a number of different spots. The number of beak locations 156 (six in the example chosen for purposes of disclosure) allows the rupture of frangible seam 110 to start proximate the beak 158 nearest the point of impact. This helps maintain a need for a substantially uniform downwardly directed force, regardless of where on the gate 108 that force is applied. The rupture of frangible seam 110 typically proceeds both clockwise and counterclockwise from the point of initial rupture at or near one of beaks 158 until the entire frangible seam 110 has ruptured.

FIGS. 1A and 2 show cover 100 in an unopened condition. Referring now to FIGS. 4B-4I, there are shown a series of side elevational, cross-sectional, schematic views of the simplified light weight, hinged, self-closing container cover 100 of FIG. 1A illustrating steps of the initial opening and self-closing of cover 100. Note that container sides 118 a, 118 b are partially shown in FIG. 4B. As previously stated, container walls 118 a, 118 b form no part of the present invention.

In operation, cover 100 is first opened by a downward pressure on gate 108 as indicated by arrow 140. As previously discussed, typically downward pressure is supplied by the heal of a hand of a person, not shown, opening the container. In FIG. 4B it may readily be seen that frangible seam 110 a has started to rupture at a point shown by arrow 160 in response to downward force indicated by arrow 140. Note that frangible seam 110 b is as yet unaffected by the downward pressure indicated by arrow 140.

In FIG. 4C, the rupture of frangible seam 110 a continues and the left edge of gate 108 has moved further inward into the container represented by container side walls 118 a, 118 b. Note that frangible seam 110 b is still unaffected by the downward pressure indicated by arrow 140.

In FIG. 4D, the rupture of frangible seam 110 a continues and the left edge of gate 108 has moved still further inward into the container represented by container side walls 118 a, 118 b. Note that frangible seam 110 b is still unaffected by the downward pressure indicated by arrow 140.

In FIG. 4E, frangible seam 110 b has finally ruptured at a position shown by arrow 162 and the left edge of gate 108 begins to rise upward, pivoting on heal of the palm of the person opening the container in response to a restoring force provided by flex-torsion spring 112. The gap in frangible seam 110 a has begun to close.

In FIG. 4F, the gap at location 162 continues to widen in response to continued downward force and the left edge of gate 108 continues to rise in response to a restoring force provided by flex-torsion spring 112. The gap in frangible seam 110 a continues to close.

In FIG. 4G, frangible seam 110 a returns to an original position as shown by arrow 164.

In FIG. 4H, downward pressure shown at arrow 140 is removed and an upward (i.e., restoring force) supplied by flex-torsion spring 112 moves the right edge of gate 108 upwards in a direction shown by arrow 166.

Finally in FIG. 4I, the gate 108 is returned to a position similar to its unopened position (FIG. 1A) and the gate effectively reseals the container cover 100.

Referring now also to FIG. 4J, once curved portion 148 is engaged in camming detent structure 124, gate 108 is permanently held in that open position, sometimes referred to as toggle mode.

It is possible using the design principles illustrated hereinabove to construct container covers wherein the gate covers substantially 100% (i.e., 90% or higher) of the area of the container within or including the chuck walls. Referring now also to FIG. 5A, there is shown a top plan, schematic view of a cover having a large gate, generally at reference number 200.

Cover 200 has a central gate 204 having a width shown by arrow 206. Gate 204 is surrounded by a triple fold (i.e., tri-fold) seam 210. A panel 216 surrounds triple fold seam 210 and panel 216 is surrounded by countersink 218. A peripheral seam, not shown, is formed adjacent and/or including a curl 208 when cover 200 is attached to a container body, not shown.

Referring now also to FIG. 5B, there is shown a partial side elevational, cross-sectional view of the cover 200 of FIG. 5A wherein triple fold flange or seam 212 is contained within triple fold seam 210, an enlarged detail of triple seam or flange 210 is shown in FIG. 5C.

Referring now also to FIGS. 5D, 5E, and 5F there are shown partial side elevational, cross-sectional views of the cover of FIG. 5A wherein a triple fold flange 210 is contained inside the chuck wall perimeter defined by countersink 218, and gate 204 is shown closed, partially open, and fully open, respectively.

Because of the extremely limited space imposed by a “large” gate (e.g., approximately 90% or more), spring design becomes critical. The combination flex-torsion springs for use in these designs have many constraints on their size. Nonetheless, such springs still need to perform the necessary different reclosure functions.

Referring now also to FIG. 6A, there is shown a bottom perspective, schematic view of a design for a combination flex-torsion spring suitable for use with a large gate, self-closing cover, generally at reference number 220.

Combination flex-torsion spring 220 has a central portion 222. Central portion 222 has a rear curved portion 224 adapted to conform to the curvature of tri-fold flange 210 and a front flat portion 226. A through hole 228 is placed in front, flat portion 226.

One of a pair of opposing arcuate side arms 230 a, 230 b extends from each edge of central portion 222. Each of opposing arcuate side arms 230 a, 230 b has a flattened region 232 a, 232 b, respectively, at the distal ends thereof. Each flattened region 232 a, 232 b has an elongated through hole 234 a, 234 b, respectively.

One of a pair of toggle tabs 236 a, 236 b extend upward from respective ones of the pair of opposing arcuate side arms 230 a, 230 b. Toggle tabs 236 a, 236 b are disposed approximately half way along a respective one of opposing arcuate side arms 230 a, 230 b.

Referring now also to FIG. 6B, there is shown a bottom plan view of the cover 200 of FIG. 5A with the combination flex-torsion spring 220 of FIG. 6A coupled thereto. A fastener or stake, not shown, may be placed in through hole 228 and through the gate 204. The fastener or stake is used to ensure proper registration of combination flex-torsion spring 220 during its attachment to cover 200 during the manufacturing of cover 200.

Adhesive 238 proximate each of through holes 234 a, 234 b is used to fasten flattened tip regions 232 a, 232 b to seaming panel, not specifically identified. Unlike the embodiment shown in FIGS. 5A-5F using a combination flex-torsion spring, for example, spring 112 of FIGS. 3A and 3B, there is no space to use a mechanical fastener or stake to attach flattened tip regions 232 a, 232 b to panel 210. Consequently, adhesive or a similar fastening system must be used to replace fasteners or stakes 144 (FIG. 1F). Optional holes 234 a, 234 b allow any excess adhesive 238 placed under flattened tip regions 232 a, 232 b to escape through the holes 234 a, 234 b. In addition, holes 234 a, 234 b may be used as a port to allow UV curing energy to reach the adhesive. Any suitable adhesive may be utilized in addition to UV-curable adhesives.

In operation, cover 200 is opened by a directed downward pressure on gate 204 as shown by arrow 140 typically applied at or near the center of gate 108. Upon application of directed downward pressure, frangible seam 212 ruptures, thereby allowing gate 204 to rotate downward into an interior region of the container, not specifically identified and forming no part of the invention, to which cover 200 is attached. Rotation of gate 204 must overcome the elastic resistive force provided by flex-torsion spring 220. The resilient force of the combination flex-torsion spring 220 is provided by the flexing of the spring central portion 222 relative to the opposing arcuate side arms 230 a, 230 b. Upon release of the directed downward pressure, the combination flex-torsion spring 220 retains sufficient memory to restore gate 204 to a closed position. Once the frangible seam 212 has been ruptured, a small amount of force is sufficient to re-open the gate 204 and access the contents. The pressure of a person's lip, not shown, against the top of the gate 204 is sufficient to re-open the gate 204 thereby allowing a user to drink from the container.

Upon further application of a directed downward force, the gate 204 may be further rotated downward and toward the central portion 222 of the combination flex-torsion spring 220. When the gate has opened through a sufficient angle with respect to the panel 202 not specifically identified, the exterior perimeter of the gate, not shown, is pushed past the tips of toggle tabs 236 a, 236 b. Once this is accomplished, the toggle tabs 236 a, 236 b marginally engage the upper peripheral surface of the exterior perimeter of gate 204, and provide sufficient resistive force in opposition to the spring memory provided by the flexing of spring central portion 222. In this position, the gate 204 is latched open, making it possible to drink from the container, or pour the contents out of the container. Subsequent closing of gate 204 may be accomplished by moving the container in a circular motion such that the interior liquid pushes against the bottom of the gate 204, and releases the gate 204 from the marginal engagement of the toggle tabs 236 a, 236 b.

Upon the application of additional force directed downward and toward the spring central portion, the gate 204 may be opened beyond the angle required to engage the toggle tabs 236 a, 236 b, to a position that flexes the spring central portion 222 beyond its elastic limit, allowing the container to remain permanently open.

Referring now also to FIG. 7A, there is shown a bottom perspective, schematic view of an alternate design for a combination flex-torsion spring suitable for use with a large gate, self-closing cover, generally at reference number 250.

Combination flex-torsion spring 250 has an elongated central portion 252. Central portion 252 has a rear, curved portion (i.e., flange encircling portion) 254 adapted to conform to the curvature of tri-fold flange 210, not shown in FIG. 7A, and a front, tongue-like flat portion 256. A through hole 258 is placed proximate the tip of front, flat, tongue-like flat portion 256.

One of a pair of opposing arcuate side arms 260 a, 260 b extends from each side of central portion 252. Each of opposing arcuate side arms 260 a, 260 b has a flattened region 262 a, 262 b, respectively, at the distal ends thereof. Each flattened region 262 a, 262 b has an elongated through hole 264 a, 264 b, respectively.

A pair of toggle tabs 266 a, 266 b extends upward from respective ones of the pair of opposing arcuate side arms 260 a, 260 b. Toggle tabs 236 a, 236 b are disposed approximately half way along a respective one of opposing arcuate side arms 260 a, 260 b.

Referring now also to FIG. 7B, there is shown a bottom plan view of the cover 200 of FIG. 5A with the combination flex-torsion spring 250 of FIG. 7A coupled thereto. A fastener or stake 270 is placed in through hole 258 and through the gate 204. Fastener or stake 270 is used to ensure proper registration of combination flex-torsion spring 250 during its attachment to cover 200 during the manufacturing and/or assembly of cover 200.

Adhesive 268 proximate each of elongated through holes 264 a, 264 b is used to fasten distal ends 262 a, 262 b to the panel 202 surrounding gate 204.

The operation of cover 200 with a combination flex-torsion spring 250 is almost identical to the operation of cover 200 equipped with combination flex-torsion spring 220 described in detail hereinabove. Consequently, the opening of cover 200 using combination flex-torsion spring 250 is not further described herein.

Referring now also to FIG. 8, there is shown a novel implementation of combination flex-torsion spring of 250 of FIG. 7A, generally at reference number 300.

Combination flex-torsion spring 300 is implemented by bending a length of spring wire 320 to fashion all the structural features of combination flex-torsion spring 250. The equivalent to spring central portion 252 of spring 250 is included within the area enclosed by dashed oval 302.

Flange encircling section 254 of combination flex-torsion spring 250 is shown at reference number 304 and is implemented as curved bends 304 in spring wire 320.

Flat portion of central portion 256 of combination flex-torsion spring 250 is actually space 306 between the wire portions, not specifically identified, that connects flattened region that contains hole 308 corresponding to hole 258 of combination flex-torsion spring 250.

Opposing arcuate side arms 310 a, 310 b are analogous to opposing arcuate side arms 260 a, 260 b of combination flex-torsion spring 250.

Spring wire 320 may be flattened to form flattened tip regions 312 a, 312 b that correspond to flattened tip regions 262 a, 262 b of combination flex-torsion spring 250.

Optional elongated holes 314 a, 314 b in flattened portions 312 a, 312 b, respectively, correspond to elongated holes 264 a, 264 b in combination flex-torsion spring 250.

Finally, analogous structures to toggle tabs 266 a, 266 b are formed at regions 316 a and 316 b in spring wire 320.

By choosing the spring characteristics of spring wire 320, the performance of combination flex-torsion spring 300 may match the performance of combination flex-torsion spring 250 but at a considerable savings in manufacturing cost. In use, combination flex-torsion spring 300 provides a direct “drop-in” replacement for combination flex-torsion spring 250.

Referring now also to FIG. 9A, there is shown a top perspective, schematic view of another implementation of a wide flex spring, generally at reference number 330.

Wide flex spring 330 has a central portion 332. A flange accepting section 334 is disposed rearward of a front tip, not specifically identified, and having a through hole 336 therein.

Two slots 342 a, 342 b separate a pair of shortened opposing arms 338 a, 338 b from central portion 332,

A pair of toggle tabs 340 a, 340 b is disposed on the front edges of respective ones of shortened opposing arms 338 a, 338 b.

Referring now also to FIG. 9B, there is shown a bottom plan, schematic view of a cover 346 utilizing combination flex-torsion spring 330.

Hole 336 in the tip of central portion 332 allows central portion 332 to be attached to a gate 344 by means of a fastener or stake, not shown, fastened therethrough. In alternate embodiments, an adhesive or other alternate fastening method may replace the fastener or stake to secure central portion 332 to oval, offset gate 344.

In operation, combination flex-torsion spring 330 in conjunction with cover 346 behaves very much the same as the operation of covers 200 with either spring 220 or spring 250. This operation is described hereinabove and such operational details are not further discussed or described with regard to combination flex-torsion spring 330 and cover 346.

Since other modifications and changes varied to fit particular operating requirements and environments will be apparent to those skilled in the art, the invention is not considered limited to the example chosen for purposes of disclosure, and covers all changes and modifications which do not constitute departures from the true spirit and scope of this invention.

Having thus described the invention, what is desired to be protected by Letters Patent is presented in the subsequently appended claims. 

What is claimed is:
 1. A combination flex and torsion spring, comprising: a) a central portion having a pair of opposing side edges, a front edge a rear edge, and means for fastening said central portion to an external surface; b) a pair of elongated, arcuate arms, each having a proximal end and a flattened region adjacent a distal end thereof, a first of said pair of elongated, arcuate arms being attached to a first of said pair of opposing side edges and extending outwardly therefrom, a second of said pair of elongated, arcuate arms being attached to a second of said pair of opposing side edges and extending outwardly therefrom; and c) a camming structure operatively connected to said central portion proximate said front edge of said central portion.
 2. The combination flex and torsion spring as recited in claim 1, wherein said central portion comprises an elongated, tongue-like forward projecting flex spring portion extending from said front edge of said central portion.
 3. The combination flex and torsion spring as recited in claim 2, wherein said elongated, tongue-like forward projecting flex spring portion comprises a distal end having a through hole therethrough.
 4. The combination flex and torsion spring as recited in claim 2, further, comprising: d) at least one through hole in at least one of the locations selected from the group: said flattened region of said first of said pair of elongated, arcuate arms, said flattened region of said second of said pair of elongated, arcuate arms, a distal end of said forward facing flex spring portion, and said central region; and e) means for fastening associated with and operatively connected to said at least one of said at least one through hole.
 5. The combination flex and torsion spring as recited in claim 4, wherein said means for fastening comprises at least one selected from the group: a fastener, a stake, and a quick cure adhesive.
 6. The combination flex and torsion spring as recited in claim 1, wherein said combination flex and torsion spring is formed from a thin piece of aluminum.
 7. The combination flex and torsion spring as recited in claim 6, wherein said thin piece of aluminum comprises one of the forms selected from the group: an aluminum sheet, and an aluminum spring wire.
 8. The combination flex and torsion spring as recited in claim 6, wherein said thin piece of aluminum comprises a 5052-H10 aluminum alloy.
 9. The combination flex and torsion spring as recited in claim 5, wherein said selected thin piece of aluminum has a thickness in the range of approximately 0.006 inch to 0.007 inch.
 10. The combination flex and torsion spring as recited in claim 1, further comprising: d) a pair of detent tabs operatively attached to respective ones of said pair of arcuate elongated arms, a first of said pair of detents being attached to a first of said pair of arcuate elongated arms and a second of said pair of detent tabs being attached to a second of said pair of arcuate elongated arms.
 11. The combination flex and torsion spring as recited in claim 10, wherein said camming structure comprises a curvilinear portion sized and configured to capture and retain a portion of at least one of said pair of detent tabs when a gate of a container cover to which said combination flex and torsion spring is attached is opened and moved to a predetermined position. 